Field of the Invention
This invention relates to a component built-in board mounting body in which a component built-in board having an electronic component built in thereto is mounted on a mounting board, and a method of manufacturing the same, and to a component built-in board.
Description of the Prior Art
In recent years, miniaturization or higher levels of integration are being required in electronic components of semiconductors and the like, and there is a tendency to increasingly adopt three-dimensional packaging technology such as CoC (Chip on Chip) and PoP (Package on Package), and component built-in boards having an electronic component built in thereto. In these packaging technologies, and so on, it becomes important that structural design takes sufficient account of heat radiation characteristics of the built in electronic component.
In a generally-employed electronic component configured from a silicon semiconductor, there is a possibility that when, for example, Tj temperature (semiconductor element temperature) attains 175° C. or more, the semiconductor element itself is destroyed, hence thermal design is performed such that Tj temperature is in a range of 80° C. to 100° C. Specifically, in a component built-in board, structural design taking account of heat radiation characteristics is important since a periphery of the built in electronic component (IC chip or passive component) is covered by an insulating resin material (for example, an epoxy resin or polyimide resin whose heat transmission coefficient is approximately 0.2 W/mk). The insulating resin material has a heat transmission coefficient which is about one thousandth ( 1/1000) compared to that of a wiring metal material (for example, copper whose heat transmission coefficient is approximately 370 W/mk).
A known electronic component built-in type wiring board that takes account of heat radiation characteristics in this way is the electronic component built-in type wiring board disclosed in Japanese Unexamined Patent Application Publication No. 2008-205124 A. This electronic component built-in type wiring board has a structure in which by forming a thermal via on a surface on an opposite side to an electrode formation surface of the built in electronic component, heat of the electronic component is radiated from this thermal via to external air via a heat radiation board in a surface layer.